This invention relates to novel bicyclictriarylphosphites, processes for their manufacture, and their use in thermoplastic and thermoset formulations.
Tris(2,4-di-tert-butylphenyl)phosphite, a commercial antioxidant, exhibits relative ineffectiveness as a process stabilizer and color suppressant in polyolefin-based formulations In part, the ineffectiveness of this phosphite is due to its lack of good thermal and/or hydrolytic stability under polyolefin processing conditions. Under these conditions, this phosphite has a tendency to molecularly fragment, thereby yielding molecular fragments having a lower molecular weight than the original molecule. These molecular fragments are generally more volatile than the original molecule and thus can be lost from the formulation during processing. With these losses, the final product made from the formulation is deficient in the antioxidant loading needed. The molecular fragmentation is illustrated by the following scheme shown for hydrolytic fragmentation, ##STR1##